A cluster of purple crystals with jagged surfaces sits on a black background, illustrating the result of the crystallization process.

How Do Crystals Form?

Salt, sugar, microprocessors, and gemstones all have something in common: crystals.
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Transcript

Crystals from table salt and sugar to computer microprocessors and gemstones, these captivating compounds are all around us.

Have you ever wondered how they form?

Many crystals actually are the results of chemical reactions!

When certain chemicals are combined in a saturated solution, the reaction produces a solid substance called a precipitate.

A precipitate is a solid compound that forms when two different kinds of dissolved ions bump into one another in a solution. The resulting precipitate is said to come out of a solution, and the process can easily be observed in the chemistry lab and in nature.

Some precipitates are crystals. Through the process of crystallization, microscopic compounds are rearranged from a liquid saturated solution into these highly ordered solid structures.

Crystallization often occurs when the saturated solution cools or evaporates.

Take note of the crystals around you. How do you think they were formed?